Zsh Configuration

Ansible

To install this Zsh configuration:

$ ansible-playbook main.yaml --ask-become-pass

Prompt

A custom prompt theme called "fresh" is used by default, its defined in prompt_fresh_setup and symbolic linked to ~/.local/share/zsh/site-functions which is on the fpath. The prompt enabled using prompt fresh when the prompt subsystem is enabled. The prompt is multi-line and does not redraw during command editing. The first line of the prompt is drawn using a precmd hook and displays variable length information such as the time, current directory, Git repository branch and status, and the last commands exit code if its non-zero.

Git Status

The "fresh" theme supports displaying Git repository status information, the majority of this information is gathered using a C program which is compiled on the fly when the theme is enabled, it resides in ~/.cache/zsh/git-prompt and is removed when the theme is disabled. Since the C program uses the standard library, development headers must be present in addition to the compiler.

zsh-git-prompt was originally used but proved to be agonisingly slow on large repositories containing many unstaged changes. Instead the git-prompt C program calls git status --porcelain, which is extremely fast, and parses the output in a loop. Output from git-prompt is a space separated list of interesting numbers which is captured in a Zsh array and interpreted for display. This results in no noticeable lag when redrawing the prompt.

Plugins

Plugins are sourced manually and their git repositories tracked by conduit, no plugin manager is used.

• zsh-autosuggestions Fish-like autosuggestions for zsh.
• zsh-syntax-highlighting Fish shell like syntax highlighting for Zsh.
• zsh-history-substring-search Zsh port of the Fish shell's history search.

In addition to third party plugins the following are custom plugins residing in this repository.

• autoenv is a inspired by zsh-autoenv but simplified by removing customization points and using a less intrusive UI.
• build is a collection of commands to make it easier to build projects focuses on C/C++ development.
• sandbox is a command which sets up a throw away directory for quickly testing ideas.
• layout is a command which setups up tmux panes in a window with scripts.
• notes is a command to quickly edit markdown note files.

Environment & Settings

The bulk of, if not all, configuration occurs in zshenv and zshrc these files.

~/.local

In addition to /usr/local add ~/.local to useful environment variables. This is especially useful with pip install --user <package>.

• Add ~/.local/share/zsh/site-functions to fpath
• Add ~/.local/bin to PATH
• Add ~/.local/share/man to MANPATH
• Add ~/.local/share/info to INFOPATH

History

Command history is stored in ~/.cache/zsh/histfile, duplicates are removed, and multi-terminal history support is enabled.

Line Editor

The vi mode line editor is enabled. zsh-vim-mode was a reasonable starting point but was replaced as it uses some strange defaults.

Cursor Shape

In order to easily ascertain which vi mode the line editor is currently using escape sequences are sent to the terminal emulator on certain events to change the current shape of the cursor. Two cursor shapes are used; block for vicmd mode; a vertical line for viins mode. Additional escape sequences are used when tmux is detected to ensure the terminal emulator receives the appropriate sequence. iTerm2 and VTE compatible terminal emulators are supported.

Three hooks are registered with the line editor; zle-keymap-select changes the cursor shape then the mode is changed; zle-line-init changes the shape starting editing a new command; and zle-line-finish resets the cursor shape when the line edit is complete.

vicmd Mode

Undo and repo and enabled using u and U. Showing help for the command under the cursor with <Esc>h is replaced with K. The Vim "Ex" mode binding : is disabled mode since is barely of use and easy to enter accidentally. Bindings for k and j integrate with zsh-history-substring-search performing up and down searches respectively.

Edit Command Line

When editing a command using Zsh's line editor becomes cumbersome due to length the <Ctrl>+V binding opens the default editor (Vim) to edit the current command.

Miscellaneous

Interactive comments are enabled, useful when creating demo GIF's of terminal program usage. Ignore end of file, bound to <Ctrl>+D, is disabled to avoid accidentally exiting the terminal.

Audio beeps are disable. Terminal flow control is disabled, this allows Vim and other terminal programs to use <Ctrl>+S mapping/binding, this proves useful as the S key is in the middle of the home row on QWERTY keyboards.

Completion

The completion subsystem is enable, any custom completions should be symbolic linked to ~/.local/share/zsh/site-functions.

Aliases

Various aliases are defined at the end of zshrc for convenience.